If the author just wanted to add a citation to some canonical paper (like "Attention is all you need") at the last minute, used LLM autocomplete to do it, and didn't carefully check that the citation was correct, then a year-long ban is a massive overreaction. A careless miscitation is not on the same level as something like data manipulation.
In general, I think everyone needs to be practical about what the actual risks are of LLM use. Are we worried about true nonsense flooding the arXiv? Or are we worried about tracking authorship when LLMs are involved? What's the actual concern?